Boiler with trapped circulation



(No Model.) 3 SheetsSheet 1.

J. J. HOGAN. BOILER WITH TRAPPED CIRCULATION.

No. 425,944. Patented Apr. 15, 1890.

(No Model.) '3 Shee tS Sheet 2.

J. J. HOGAN. BOILER WITH TRAPPED GIRGULATIQN. No. 425,944.

Patented Apr. 15, 1890.

me humus versus cm. Mauro-mum, wAsI-umron, o. c.

(No Model.) 3 Sheets-Sheet 3. J. J. HOGAN.

BOILER WITH TRAPPED CIRCULATION.

No. 425,944. Patented Apr. 15. 1890.

&

UNITED STATES PATENT OFFICE.

JOHN'J. HOGAN, OF BROOKLYN, NEW' YORK, ASSIGNOR TO THE HOGAN ENGINEERINGCOMPANY, OF NEW YORK.

BOILER WITH TRAPPED CIRCULATION.

SPECIFICATION forming part of Letters Patent No. 425,944, dated April15, 1890. Application filed December 9, 1889.. Serial No. 333,145. (Nomodel.)

To aZZ whom it may concern:

Be it known that I, JOHN J. HOGAN, a citizen of the United States,residing at Brooklyn, Kings county, New York, have invented certain newand useful Improvements in Boilers with Trapped Circulation, fullydescribed and represented in the following specification and theaccompanying drawings, forming a part of the same.

My invent-ion is particularly adapted for heating water to circulatethrough radiators, in which case the generation of steam in the boileris undesirable; and its object is to promote an upward circulationwithin the boiler over the hottest part of the fire, and a positivedownward circulation exterior to the Water-space of the boiler toreplace the rising fluid. The upward circulation is preferably conductedthrough a passage in the center of the boiler, because such point isover the hottest part of the fire, and the fluid moving downward is ledto conductors exterior to the boiler, that such conductors may be coolerthan the water-space of the boiler and thereby promote the movement of.the fluid downward therein. The exterior conductors are connected tothe water-space of the boiler at intervals by connections leadingdownwardly from such watersection into such conductor. The passagebetween the water-space and the exterior conductor may be confined tothe lower part of each water-section by leading the water channel orconnection from the bottom of such water-space, or by a deflecting plateor tube projecting downwardly within the upper part of suchwater-space,where it is connected with the exterior conductor. Each of theseconstructions serves alike to trap the hot water within thewater-section and prevent its rising into the exterior conductor, whilethe connection with the exterior conductor permits the free access ofcolder fluid from the conductor to thewater-section, as maybe required.By this construction the heated fluid within the boiler is preventedfrom gaining access to the exterior conductors and thus obstructing thedownward current therein, and is effectively directed toward thevertical passage or passages within the water-space in which the currentmoves naturally upward.

Cast-iron boilers have heretofore been made in horizontal sections withvertical connecting-thimbles, and the exterior of such sections has beenmade sometimes round and sometimes rectangular to form a circular or asquare boiler.

My improvements are especially adapted to boilers formed with horizontalwater-sections and intermediate smoke-chambers, but may obviously beapplied to other constructions.

In the annexed drawings, Figure 1 is an elevation of a boilerconstructed with my improvement in horizontal water-sections withintermediate smoke-chambers. Fig. 2 is a central vertical section of thesame. Fig. 3 is a plan of the same at the top of the fire-pot. Fig. 4 isa plan, partly in sectionwherehatched, of the sections above thefire-box, excepting the top one. Fig. 5 is a section, upon an enlargedscale, of part of two sections, with the external thimbles projecteddownward therein; and Fig. 6 is a similar view of two sections, withdeflectors upon their upper sides adjacent to the thimbles.

A B O D are four water-sections separated by smoke-spaces e andsustained above aflrepot by a series of water-columns p and Z. Thefire-pot is formed by a water-ring E and rests upon an ash-pit F,provided. with grate G.

Each water-section, except the section T (if such be used) at theextreme top of the boiler, is provided with apertures 11, which areextended over one another in the same vertical line to form continuousvertical smoke-fines connecting the fire-box and the intermediate spaces6 directly with the upper smoke-space II, from which the smoke isconducted by a nozzle I. Each Water-section is also provided withsmoke-apertures 1), formed to alternate with one another in the severalsections A B C D, and thus form interrupted smoke-fines, such as havebeen commonly used in similar constructions. A hollow ring containing anannular water-spacej projects down ward from the bottom of eachwater-section at its margin, and is provided with hollow lugs 7.5, whichare connected together by thimbles Z, arranged in vertical line over oneanother. The interiors of the water-sections are connected together atthe center by circular nozzles 42,

forming avertical water column or passage 17 over the center of thefire-box, and the outlet 0 of the boiler is provided in the top sectionover such central passage to discharge the heated fluid in an unbrokencurrent.

The top section T is shown as constructed merely to cover the topsmoke-space with a water-box, and the return-fluid from theheating-radiators would be connected by pipes q with the lugs 7a in suchtop section, and also with the water-rin g E around the fire-pot by anozzle q intermediate to the lugs 7c,formed.

upon the same. A smoke-aperture I is extended through the top section toconnect the boiler to a chimney-flue by a suitable pipe I.

The lugs 70, formed upon the water-ring E, are arranged in line with thecorresponding lugs upon the watersections, and are com nected thereto bythe thimbles l, which form an uninterrupted vertical column or passagefor the descent of the colder fluid. The wa ter-ring is also connectedwith the lower part of the ring j upon the section A by tubularconnections 8, which provide a passage for the upward movement of thefluid heated within the water-ring. The ring is partially lined'withfire-brick b and an aperture a for a fire-door is formed in such ringabove the fire-brick and in a portion of the annular ring j upon thelower edge of the section A, as shown in Figs. 1 and 3.

It will be noticed that the apertures 12 through the water-sectionsbeing in a direct line with one another induce a strong draft from thefire upward to the top smoke-space H, and thus operate to heat mosteffectively the central water-passage 19, while the thimbles Z beingwholly removed from the action of the fire operate as uninterrupteddescending columns for the colder fluid. When the return-current from asystem of heating-radiators is connected with the nozzle q UPODIIIBwater-ring it is immediately heated by the heat of the fire-box andrises through the connections 8 into the water-section above it.

Theonly connection from each of the water-sections with the thimbles lis through the annular water-spaces j, which are connected exclusivelywith the bottoms of the to rise upward in the boiler.

sections, and the water heated in the several sections is thus forced tomove exclusively toward the central water-channel p The movement of theheated fluid toward the center of the boiler is facilitated by slopingthe top of each of the water-sections upwardly to ward the nozzle 92.,as shown in Fig. 2. Here the central water-colun1n furnishes a directupward passage for the heated fiuid,whichis thus led to the outlet 0 inthe top section. The margin of the section (shown at Ain Fig. 2) thusoperates as a trap to obstruct any upward movement of the water withinthe water-sections toward the thimbles Z, while it doesnot in the leastiinpedea downward movement of the water from any of the sectionsto thethilnbles. \Vhen the return-fluid from the circulating system,outside'of the boiler is out ofl: from the boiler, the heat around thefire-pot would soon overheat the adjacent surfaces and injure the metalunless a free circulation of water be maintained therein. By the trappedformation of the connections between the water-sections and the thimblesZ a positive upward circulation is induced in the center of the boiler,and a positive downward circulation is induced in the thimbles. Itwill'also be noticed by reference to Fig. 2 that, while. the trappedconnection referred to impedes themovement of the hot water in any ofthe water-sections toward the lugs 70, it ofiers no obstruction. to therising of the fluid from any of the lugs into the water-section, aswould be required in the case of the section A, which receives all thereturn fluid from the waterring through the connections .9 and lowerthimbles Z.

Fig. 5 shows the lug from the edge of the water-section without anydepending water-space j, and the trapped connection between thewater-section and the thimbleis formed by projecting the end of thethimble downward within the top of the section, as shown at Z. Suchconstruction does not obstruct the downward flow of the current in thethimbles nor the upward movement of the fluid from the thimbles into thewater-section, while it does obstruct, in' the desired manner, thepassage of hotwater from the upper side of the water-section to theupper thimble.

In Fig. 6 a deflector Z is shown formed acrossthe lug 70 between theinlet of the thimble and the body of the water-section,and thus performsthe same function as the projecting end of the thimble shown at Z inFig. 5.

It will be noticed that all the constructions shown in Figs. 2, 5, and 6operate alike as deflectors projecteddownward in the connections betweenthe water-sections and the external conductor or thimble, and thusprevent the upward movement of the fluid from the water-space to theconductors. The waterconneet-iou from the section to the interior of theprojectinglug 70 may thus be said to lead downwardly, and furnishes apassage opposed to the outward movement of the heated fluid, which morenaturally moves upward within the boiler under the pressure of thecolder fluid, which may press upon it.

While the smoke-apertures b, by their arrangement in the severalsections, obstruct the direct flow of the heated gases, the apertures Z)serve to carry theheated gas from the fire-pot directly upward in closecontact with the central water-channel p, and I therefore consider thecombination of such direct and indirect smoke-passages as serving avaluable purpose in connection with the-trapped circulation of theboiler.

Fig. 4 is drawn, in section at the right-hand side to showthewater-space between the apertures b and b and to exhibit a guard '10,which is shown extended within the margin of the section at the inneredge of the depending hollow ring, which forms the annular waterspace j.This guard, when used, operates to prevent the direct flow of the fluidto or from the thimbles Z, and compels the circulation from the thimblesto the central nozzles to pass around the ends of the guard to reach thelatter.

I find a great advantage in the sloping top upon each of thewater-sections, as shown in Figs. 2, 5, and 6, when used in combinationwith the external conductors, which are connected with such sections bythe downward passages employed in my construction. By such constructionand by the provision of a large vertical passage within the boiler likethe central water-column p, I furnish ample facilities for the upwardmovement of the water over the hottest part of the fire, while theexterior conductors furnish a suitable channel or water-column for thedownward movement of the fluid to maintain a circulation within theboiler when the disuse of the external heating system necessitates sucha circulation. I thuswholly prevent the overheating of the boiler in anypart, while I increase its evaporative power.

The hollow ring shown herein projected downward from the margin of eachsection is made circular in form to correspond with the shape of thesection; but it is obvious that such ring is in function a Water-leg,and that a precise equivalent for such hollow ring could be formed uponthe margin of a square section and projected downward, and furnishedwith connections to the external conductors in the manner hereindescribed. I

therefore consider that a water-leg, formed upon a square rim. andconnected like the hollow ring shown in my drawings, would be a preciseequivalent therefor, and would be covered by my claims herein.

I hereby disclaim my pending application No. 332,697, filed December 5,1889, as I have shown and described herein certain features which areclaimed in the said application.

In my pending application, Serial No. 382,697, filed December 5, 1889, Ihave shown a boiler constructed substantially like that in my presentdrawings, and have claimed a Water-jacket connected with the edge ofeach section and two or more vertical water-com nections between thesections to provide for upward and downward circulation. I have alsoclaimed in connection with such waterjacket a vertical water-connectionbetween the sections inside the same and a vertical water-connectionbetween the sections external to the same, and to such constructions Imake no claim in my present application.

Having thus set forth my invention, what I claim herein is 1. In aboiler, the combination, with one or more water-passages extendingvertically within the boiler, of one or more water-conductors exteriorto the water-space of the boiler,connections at intervals between theexternal conductors and the water-space of the boiler, and deflectorsprojected downward in such connections to prevent the upward movement offluid from the water-space to the conductors, substantially as hereinset forth.

2. In a boiler comprising a series of watersections separated byintermediate smokechambers, the combination, with one or morewater-passages extending vertically within theboiler, of one or morewater-conductors exterior to the water-space of the boiler, connectionsbetween the external conductors and the water-sections, and deflectorsprojected downward in such connections to prevent the upward movement ofthe fluid from the waterspace to the conductors, substantially as hereinset forth.

3. In a boiler comprising a series of watersections separated byintermediate smokechambers, the combination, with awater-passageextending vertically within the boiler through the centers of thewater-sections, of one or more water-conductors exterior to thewater-space of the boiler, connections between the external conductorsand the watersections, and deflectors projected downward in suchconnections to prevent the upward movement of the fluid from thewater-space to the conductors, substantially as herein set forth.

4:. In a cast-iron boiler, the combination of a series of horizontalwater-sections having one or more vertical passages connecting the samefor the internal upward movement of the fluid, and each section beingprovided with exterior lugs connected by thimbles, and thewater-connection between the section and theinterior of such lug leadingdownwardly, as and for the purpose set forth.

5. In a cast-iron boiler, the combination of a series of horizontalwater-sections having central water-connections for the upward passageof the fluid, and exterior water-connections for the downward passage ofthe fluid, one series of smoke-apertures through all the sections in thesame vertical line to form uninterrupted smoke-flues, and a series ofapertures arranged alternately in the several sections to forminterrupted smokeflues, as and for the purpose set forth.

6. In a cast-iron boiler, the combination, with a series of horizontalwater-sections having apertures through them for the passage of smoke,and one or more vertical passages connecting the said sections for theupward movement of the fluid, of a hollow ring projected downward fromthe margin of each section, and water-connections between such dependingrings for the downward movement of the fluid, as and for the purpose setforth.

7. In a cast-iron boiler, the combination 'of a series of water-sectionsperforated with vertical smoke-apertures, and provided at the centerwith nozzles to form a vertical waterpassage, the sections havingexternal hollow lugs connected 111 a series; by means; of t liim-:terior to the sect-ionswithpassages leading 1 I ,bles, .an-dbeing:provided with guards wwithdownwardly from zeaehiseebion into sueh-ex- Iin the margin ofthesections adjacent to such I :terior conductors,substantially as herei n' sefi l lugsto prevenhthedirectpassageoflth'efiuid forth.2 J; -5- he. hi -nblefi,Substantially.as.herein set -1-I11 testimony whereofl have LhGlBl'lfitOSGt iGlt-llww myhand'in the-presence 0f twosuhscribing 8;Thecomhinatiominab0i1er,0fa-series witnesses." 2 I of water-sectionshaving: domed; or :sloping -mp5,withwaterrconnectionsforming: ac0n-'""Witnesses: 1o tinuouspassage throughrt-he centers of the *AO.'KITTREDGE, sections, andvertical' water-conductors ex- I THOS. S;CRANE;

